Ataxia Telangiectasia and Rad3-Related Activation by DNA Damage Mitigates Maladaptive Repair after Acute Kidney Injury

DNA damage is an important consequence of injury to the proximal tubule. The proximal tubule cell responds to this damage by mounting a DNA damage response (DDR). Two protein kinases, ataxia-telangiectasia mutated (ATM) or ataxia telangiectasia and Rad3-related (ATR), play an important role in this DDR. If efficient, the DDR can lead to repair of the DNA, cell renewal, and return to a healthy state. In many cases, however, especially in the setting of baseline kidney injury, there is incomplete repair. In human chronic kidney disease (CKD) and in human kidney organoids exposed to acute injury, there is increased evidence of DNA damage and activation of ATR. This review focuses on 3 aspects of the DNA damage and response to it: (1) DNA damage and the DDR precipitated by acute injury; (2) protection afforded by the DDR kinase, ATR, in multiple mouse models of acute kidney injury; and (3) downstream effects of genetic inhibition of ATR in the proximal tubule, leading to maladaptive repair, fibrosis, and CKD.